/*
 * Distributed as part of c3p0 v.0.9.5.2
 *
 * Copyright (C) 2015 Machinery For Change, Inc.
 *
 * Author: Steve Waldman <swaldman@mchange.com>
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of EITHER:
 *
 *     1) The GNU Lesser General Public License (LGPL), version 2.1, as 
 *        published by the Free Software Foundation
 *
 * OR
 *
 *     2) The Eclipse Public License (EPL), version 1.0
 *
 * You may choose which license to accept if you wish to redistribute
 * or modify this work. You may offer derivatives of this work
 * under the license you have chosen, or you may provide the same
 * choice of license which you have been offered here.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * You should have received copies of both LGPL v2.1 and EPL v1.0
 * along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
 * If not, the text of these licenses are currently available at
 *
 * LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 *  EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php 
 * 
 */

package com.mchange.v2.c3p0.impl;

import com.mchange.v2.coalesce.*;

public final class IdentityTokenizedCoalesceChecker implements CoalesceChecker
{
    public static IdentityTokenizedCoalesceChecker INSTANCE = new IdentityTokenizedCoalesceChecker();

    public boolean checkCoalesce( Object a, Object b )
    {
	IdentityTokenized aa = (IdentityTokenized) a;
	IdentityTokenized bb = (IdentityTokenized) b;
	
	String ta = aa.getIdentityToken();
	String tb = bb.getIdentityToken();
	
	if (ta == null || tb == null)
	    throw new NullPointerException( "[c3p0 bug] An IdentityTokenized object has no identity token set?!?! " + (ta == null ? ta : tb) );
	else
	    return ta.equals(tb);
    }
    
    public int coalesceHash( Object a )
    { 
	String t = ((IdentityTokenized) a).getIdentityToken();
	return (t != null ? t.hashCode() : 0); 
    }

    private IdentityTokenizedCoalesceChecker()
    {}
}
